Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!decwrl!decvax!ucbvax!QUABBIN.SCRC.SYMBOLICS.COM!DCP
From: DCP@QUABBIN.SCRC.SYMBOLICS.COM (David C. Plummer)
Newsgroups: comp.protocols.tcp-ip
Subject: Zero windows in SUN Unix
Message-ID: <19880204141832.4.DCP@SWAN.SCRC.Symbolics.COM>
Date: 4 Feb 88 14:18:00 GMT
References: <2644@dcatla.UUCP>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 21


    Date: 3 Feb 88 19:18:16 GMT
    From: dcatla!dnwcv@gatech.edu  (William C. VerSteeg)

    Is this closed window scenario common? Would it be advisable to reduce the 
    terminal server's timer length from 2 minutes to something like 10 seconds?

My opinion is that the terminal server should know little if anything
that it is talking to a TCP stream as opposed to any other kind of
stream.  It should be the stream's (TCP in this case) responsibility to
let the program (the terminal server in this case) let one more byte
pass through (because that is how TCP works) which will get the flow of
data working again.  Under this scenario, you needn't change the
terminal server, only the variable that controls the timeouts for all of
TCP.

Another opinion is that when the TCP data receiver has acknowledged all
the data yet still offers a zero window, the sender should be allowed to
send the one byte probe immediately, instead of having to wait for a
timer to go off.  Again, this is at the TCP stream level, not at the
level of any program.